Contraction (childbirth)

In medicine (obstetrics), a contraction is a forceful and painful motion of the uterus as part of the process of childbirth. Contractions, and labor in general, is one condition that releases the hormone oxytocin into the body.Prior to actual labor, women may experience Braxton Hicks contractions, sometimes known as "false labor."The uterus also contracts during menstruation. These contractions may be uncomfortable or even painful, but they are generally significantly less painful than contractions during labor.
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